Before: Pasta Bolognese. More meat than actual sauce, Bolognese sings with fatty cuts of beef and pork, then sits atop a mountain of white pasta. To flip, we "beef up" just 6 ounces of sirloin with loads of mushrooms, aromatics, and walnuts.
Just when you think there isn't enough veggie goodness, we pack even more into the base disguised as "boodles" (butternut noodles), intertwined with whole-grain pasta. You'll need a spiralizer or julienne peeler to make the veggie noodles. The meaty texture and nutty flavor from the walnuts is downright addictive.
Pour boiling water over porcini in a small bowl; let stand 15 minutes. Remove porcini with a slotted spoon; finely chop porcini, and reserve soaking liquid.
Heat a large skillet over medium heat. Add oil to pan; swirl to coat. Add onion, carrot, and celery; cook 5 minutes, stirring occasionally. Add cremini mushrooms and garlic; cook 6 minutes or until mushroom liquid evaporates, stirring occasionally. Add beef; cook 3 minutes, stirring frequently. Add tomato paste; cook 1 minute, stirring constantly. Stir in porcini, oregano, salt, pepper, and tomato sauce; pour in porcini liquid, stopping before grit at bottom of bowl reaches sauce. Bring to a boil; reduce heat, and simmer, uncovered, 12 minutes or until thickened, stirring occasionally to keep sauce from sticking.
Run squash through a spiralizer to create noodles, or cut into long noodles with a julienne peeler; set aside. Cook pasta according to package directions, omitting salt and fat, and adding butternut noodles during last 2 minutes of cooking time. Drain.
Stir walnuts into sauce; spoon over pasta mixture. Sprinkle with cheese.